From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1888) id EADAA3857022; Thu, 24 Jun 2021 15:29:58 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org EADAA3857022 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Patrick Palka To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-1792] c++: requires-expression folding [PR101182] X-Act-Checkin: gcc X-Git-Author: Patrick Palka X-Git-Refname: refs/heads/master X-Git-Oldrev: 178fb8df9315f2f8f45b7fe5faf11a9c2912cc28 X-Git-Newrev: c06493dc30afbf65b14d783c7cd53f20877ef577 Message-Id: <20210624152958.EADAA3857022@sourceware.org> Date: Thu, 24 Jun 2021 15:29:58 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Jun 2021 15:29:59 -0000 https://gcc.gnu.org/g:c06493dc30afbf65b14d783c7cd53f20877ef577 commit r12-1792-gc06493dc30afbf65b14d783c7cd53f20877ef577 Author: Patrick Palka Date: Thu Jun 24 11:29:02 2021 -0400 c++: requires-expression folding [PR101182] Here we're crashing because cp_fold_function walks into the (templated) requirements of a requires-expression outside a template, but the folding routines aren't prepared to handle templated trees. This patch fixes this by making cp_fold use evaluate_requires_expr to fold a requires-expression as a whole, which also means we no longer need to explicitly do so during gimplification. (Note that we delay folding of such requires-expressions for sake of better diagnostics when one is used as the condition of a failed static_assert.) PR c++/101182 gcc/cp/ChangeLog: * constraint.cc (evaluate_requires_expr): Adjust function comment. * cp-gimplify.c (cp_genericize_r) : Move to ... (cp_fold) : ... here. gcc/testsuite/ChangeLog: * g++.dg/cpp2a/concepts-requires25.C: New test. Diff: --- gcc/cp/constraint.cc | 2 +- gcc/cp/cp-gimplify.c | 10 ++++------ gcc/testsuite/g++.dg/cpp2a/concepts-requires25.C | 10 ++++++++++ 3 files changed, 15 insertions(+), 7 deletions(-) diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc index 74b16d27101..286332ba2a7 100644 --- a/gcc/cp/constraint.cc +++ b/gcc/cp/constraint.cc @@ -3340,7 +3340,7 @@ evaluate_concept_check (tree check) } /* Evaluate the requires-expression T, returning either boolean_true_node - or boolean_false_node. This is used during gimplification and constexpr + or boolean_false_node. This is used during folding and constexpr evaluation. */ tree diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c index 96d91b6ef2f..33e10556e32 100644 --- a/gcc/cp/cp-gimplify.c +++ b/gcc/cp/cp-gimplify.c @@ -1465,12 +1465,6 @@ cp_genericize_r (tree *stmt_p, int *walk_subtrees, void *data) TARGET_EXPR_NO_ELIDE (stmt) = 1; break; - case REQUIRES_EXPR: - /* Emit the value of the requires-expression. */ - *stmt_p = evaluate_requires_expr (stmt); - *walk_subtrees = 0; - break; - case TEMPLATE_ID_EXPR: gcc_assert (concept_check_p (stmt)); /* Emit the value of the concept check. */ @@ -2708,6 +2702,10 @@ cp_fold (tree x) x = r; break; + case REQUIRES_EXPR: + x = evaluate_requires_expr (x); + break; + default: return org_x; } diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-requires25.C b/gcc/testsuite/g++.dg/cpp2a/concepts-requires25.C new file mode 100644 index 00000000000..90cbedb51d4 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-requires25.C @@ -0,0 +1,10 @@ +// PR c++/101182 +// { dg-do compile { target concepts } } + +int a; +void g(bool); + +bool f() { + g(requires { a++; }); + return requires { a++; }; +}